38CKC, 38CKG, 38CKS, 38CKW10 SEER Split System

Air Conditioner

Installation and Start-Up Instructions

NOTE: Read the entire instruction manual before starting theinstallation.

This symbol → indicates a change since the last issue.

SAFETY CONSIDERATIONSImproper installation, adjustment, alteration, service, maintenance,or use can cause explosion, fire, electrical shock, or otherconditions which may cause death, personal injury, or propertydamage. Consult a qualified installer, service agency, or yourdistributor or branch for information or assistance. The qualifiedinstaller or agency must use factory-authorized kits or accessorieswhen modifying this product. Refer to the individual instructionspackaged with the kits or accessories when installing.

Follow all safety codes. Wear safety glasses, protective clothing,and work gloves. Use quenching cloth for brazing operations.Have fire extinguisher available. Read these instructions thor-oughly and follow all warnings or cautions included in literatureand attached to the unit. Consult local building codes and NationalElectrical Code (NEC) for special requirements.

Recognize safety information. This is the safety-alert symbol .When you see this symbol on the unit and in instructions ormanuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and CAU-TION. These words are used with the safety-alert symbol. DAN-GER identifies the most serious hazards which will result in severepersonal injury or death. WARNING signifies hazards whichcould result in personal injury or death. CAUTION is used toidentify unsafe practices which would result in minor personalinjury or product and property damage. NOTE is used to highlightsuggestions which will result in enhanced installation, reliability,or operation.

Before installing, modifying, or servicing system, main elec-trical disconnect switch must be in the OFF position. Theremay be more than 1 disconnect switch. Lock out and tagswitch with a suitable warning label. Electrical shock cancause personal injury or death.

INTRODUCTION AND RECOMMENDATIONSNOTE: In some cases noise in the living area has been traced togas pulsations from improper installation of equipment.

1. Locate unit away from windows, patios, decks, and so forth,where unit-operation sound may disturb customer.

2. Ensure that vapor- and liquid-tube diameters are appropriate tocapacity of unit. (See Table 1.)

3. Run refrigerant tubes as directly as possible by avoidingunnecessary turns and bends.

4. Leave some slack between structure and unit to absorbvibration.

5. When passing refrigerant tubes through the wall, seal openingwith RTV or other pliable silicon-based caulk. (See Fig. 3.)

6. Avoid direct tubing contact with water pipes, duct work, floorjoists, wall studs, floors, and walls.

7. Do not suspend refrigerant tubing from joists and studs with arigid wire or strap that comes in direct contact with tubing.(See Fig. 3.)

8. Ensure that tubing insulation is pliable and completely sur-rounds vapor tube.

9. When necessary, use hanger straps which are 1 in. wide andconform to shape of tubing insulation. (See Fig. 3.)

Fig. 1—Model 38CKC

A97005

Fig. 2—Models 38CKG, 38CKS, 38CKW

A98525

Visit www.carrier.com

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Book 1 4Tab 3a 2a

PC 101 Catalog No. 533-80008 Printed in U.S.A. Form 38CKC-3SI Pg 1 4-01 Replaces: 38CKC-2SI

10. Isolate hanger straps from insulation by using metal sleevesbent to conform to shape of insulation.

When outdoor unit is connected to factory-approved indoor unit,outdoor unit contains system-refrigerant charge for operation withindoor unit of the same size when connected by 15 ft offield-supplied or factory-accessory tubing. For proper unit opera-tion, check refrigerant charge using charging information locatedon control-box cover and/or in the Check Charge section of thisInstruction.

IMPORTANT: Maximum liquid-line size is 3/8-in. O.D. for allresidential applications including long line.

IMPORTANT: Always install a liquid-line filter drier. Refer toProduct Data Digest for appropriate part number. Obtain filterdriers from your local distributor or branch.

INSTALLATION

Step 1—Check Equipment and Job Site

UNPACK UNIT

Move to final location. Remove carton, taking care not to damageunit.

INSPECT EQUIPMENT

File claim with shipping company prior to installation if shipmentis damaged or incomplete. Locate unit-rating plate on unit-cornerpanel. It contains information needed to properly install unit.Check rating plate to be sure unit matches job specifications.

Step 2—Install on a Solid, Level Mounting Pad

If conditions or local codes require the unit be attached to pad,tie-down bolts should be used and fastened through knockoutsprovided in unit base pan. Refer to unit-mounting pattern in Fig. 4to determine base-pan size and knockout-hole location.

On rooftop applications, mount on level platform or frame. Placeunit above a load-bearing wall and isolate unit and tubing set from

structure. Arrange supporting members to adequately support unitand minimize transmission of vibration to building. Consult localcodes governing rooftop applications.

Roof-mounted units exposed to winds above 5 mph may requirewind baffles. Consult Low-Ambient Guideline for wind-baffleconstruction.

NOTE: Unit must be level to within ± 2° (± 3/8 in./ft) percompressor manufacturer specifications.

Step 3—Clearance Requirements

When installing, allow sufficient space for airflow, wiring, refrig-erant piping, and service. Allow 30-in. clearance to service end ofunit and 48 in. above unit. For proper airflow, a 6-in. clearance on1 side of unit and 12 in. on all remaining sides must be maintained.Maintain a distance of 24 in. between units. Position so water,snow, or ice from roof or eaves cannot fall directly on unit.

On rooftop applications, locate unit at least 6 in. above roofsurface.

Step 4—Operating Ambients

The minimum outdoor-operating ambient in cooling mode is 55°F,and the maximum outdoor-operating ambient in cooling mode is125°F.

Step 5—Check Indoor AccuRaterT Piston

Check indoor-coil piston to see if it matches the required pistonshown on outdoor unit-rating plate. If it does not match, replaceindoor-coil piston with piston shipped with outdoor unit. Thepiston shipped with outdoor unit is correct for any approvedindoor-coil combination.

Fig. 3—Connecting Tubing Installation

A94028

INSULATION

VAPOR TUBE

LIQUID TUBE

OUTDOOR WALL INDOOR WALL

LIQUID TUBE

VAPOR TUBEINSULATION

CAULK

Avoid contact between tubing and structureNOTE:

THROUGH THE WALL

HANGER STRAP(AROUND VAPOR

TUBE ONLY)

JOIST

1″ MIN.

SUSPENSION

Fig. 4—Mounting Unit to Pad

Dimensions (In.)

UNIT SIZEMINIMUM

MOUNTING PADDIMENSIONS

TIEDOWN KNOCKOUT LOCATIONS

A B C

018, 024-C/G/W18 X 18 3 15 10-3/16

018-CKS

030-042-C/G/W22-1/2 X 22-1/2 3-11/16 18-1/8 14-3/8

024-036-CKS

048, 060-C/G/W30 X 30 6-1/2 23-1/2 20

042-060-CKS

A94199

C

B

A

3⁄8″D. (9.53) TIEDOWN

KNOCKOUTS (2) PLACES

2

Remove indoor-coil piston if unit is to be installed on systemwith a thermostatic-expansion valve (TXV) metering device.

Step 6—Make Piping Connections

Relieve pressure and recover all refrigerant before systemrepair or final unit disposal to avoid personal injury or death.Use all service ports and open all flow-control devices,including solenoid valves.

If ANY refrigerant tubing is buried, provide a 6-in. verticalrise at service valve. Refrigerant-tubing lengths up to 36 in.may be buried without further consideration. For lengthsabove 36 in., contact your local distributor.

To prevent damage to unit or service valves observe thefollowing:•Use a brazing shield.•Wrap service valves with wet cloth or use a heat sinkmaterial.

Outdoor units may be connected to indoor section using accessory-tubing package or field-supplied refrigerant-grade tubing of cor-rect size and condition. For tubing requirements beyond 50 ft,substantial capacity and performance losses can occur. Followingthe recommendations in the Residential Split-System Long-LineApplication Guideline will reduce these losses. Refer to Table 1for field-tubing equivalent-line tube diameters. Refer to Table 2 foraccessory requirements.

If refrigerant tubes or indoor coil are exposed to atmosphere, theymust be evacuated to 500 microns to eliminate contamination andmoisture in the system.

OUTDOOR UNIT CONNECTED TO FACTORY-APPROVEDINDOOR UNIT

Outdoor unit contains correct system-refrigerant charge for opera-tion with indoor unit of same size when connected by 15 ft offield-supplied or factory-accessory tubing. Check refrigerantcharge for maximum efficiency.

REFRIGERANT TUBING

Connect tubing to fittings on outdoor unit vapor- and liquid-service valves. (See Table 1.) Use refrigerant-grade tubing. Referto appropriate section below for type of service valves installed onunit.

SWEAT CONNECTION

To avoid valve damage while brazing, service valves must bewrapped in a heat-sinking material, such as a wet cloth.

Service valves are closed from factory and ready for brazing. Afterwrapping service valve with a wet cloth, braze sweat connectionsusing industry accepted methods and materials. Consult local coderequirements. Refrigerant tubing and indoor coil are now ready forleak testing. This check should include all field and factory joints.

IMPORTANT: Check factory tubing on both indoor and outdoorunits to ensure tubes are not rubbing against each other or anysheet metal. Pay close attention to feeder tubes, making sure wireties on feeder tubes are secure and tight.

Step 7—Make Electrical Connections

To avoid personal injury or death, do not supply power to unitwith compressor terminal-box cover removed.

Be sure field wiring complies with local and national fire, safety,and electrical codes, and voltage to system is within limits shownon unit-rating plate. Contact local power company for correction ofimproper voltage. See unit-rating plate for recommended circuit-protection device.

NOTE: Operation of unit on improper line voltage constitutesabuse and could affect unit reliability. See unit-rating plate. Do notinstall unit in system where voltage or phase imbalance (3 phase)may fluctuate above or below permissible limits.

NOTE: Use copper wire only between disconnect switch andunit.

NOTE: Install branch-circuit disconnect of adequate size perNEC to handle unit-starting current. Locate disconnect within sightfrom and readily accessible from unit, per Section 440-14 of NEC.

ROUTE GROUND AND POWER WIRES

Remove access panel to gain access to unit wiring. Extend wiresfrom disconnect through power wiring hole provided and intounit-control box.

The unit cabinet must have an uninterrupted or unbrokenground to minimize personal injury if an electrical faultshould occur. The ground may consist of electrical wire ormetal conduit when installed in accordance with existingelectrical codes. Failure to follow this warning can result in anelectric shock, fire, or death.

CONNECT GROUND AND POWER WIRES

Connect ground wire to ground connection in control box forsafety. Connect power wiring to contactor as shown in Fig. 5.

Table 1—Refrigerant Connections and Recommended Liquid- and Vapor-Tube Diameters (In.)

UNITSIZE

LIQUID VAPOR VAPOR (LONG LINE)Connection Diameter Tube Diameter Connection Diameter Tube Diameter Connection Diameter Tube Diameter

018, 024 3/8 3/8 5/8 5/8 5/8 3/4030, 036 3/8 3/8 3/4 3/4 3/4 7/8042, 048 3/8 3/8 7/8 7/8 7/8 1-1/8

060 3/8 3/8 7/8 1-1/8 7/8 1-1/8

NOTES:1. Tube diameters are for lengths up to 50 ft. For tubing lengths greater than 50 ft, consult Application Guidelines and Service Manual—Air Conditioners and Heat PumpsUsing R-22 Refrigerant2. Do not apply capillary-tube indoor coils to these units.

3

CONNECT CONTROL WIRING

Route 24-v control wires through control-wiring grommet andconnect leads to control wiring. (See Fig. 7.)

Use No. 18 AWG color-coded, insulated (35°C minimum) wire. Ifthermostat is located more than 100 ft from unit, as measuredalong the control-voltage wires, use No. 16 AWG color-codedwire to avoid excessive voltage drop.

All wiring must be NEC Class 1 and must be separated fromincoming power leads.

Use furnace transformer, fan-coil transformer, or accessory trans-former for control power, 24-v/40-va minimum.

NOTE: Use of available 24-v accessories may exceed the mini-mum 40-va power requirement. Determine total transformer load-ing and increase the transformer capacity or split the load with anaccessory transformer as required.

Step 8—Compressor Crankcase Heater

When equipped with a crankcase heater, furnish power to heater aminimum of 24 hr before starting unit. To furnish power to heateronly, set thermostat to OFF and close electrical disconnect tooutdoor unit.

A crankcase heater is required if refrigerant tubing is longer than50 ft. Refer to Application Guideline and Service Manual—AirConditioners and Heat Pumps Using R-22 Refrigerant.

Step 9—Install Electrical Accessories

Refer to individual instructions packaged with kits or accessorieswhen installing.

Step 10—Start-Up

Do not vent refrigerant to atmosphere. Recover during systemrepair or final unit disposal.To prevent compressor damage or personal injury, observethe following:•Do not overcharge system with refrigerant.•Do not operate unit in a vacuum or at negative pressure.•Do not disable low-pressure switch.In scroll-compressor applications:•Dome temperatures may be hot.

To prevent personal injury wear safety glasses, protectiveclothing, and gloves when handling refrigerant and observethe following:•Back-seating service valves are not equipped with Schradervalves. Fully back seat (counterclockwise) valve stem beforeremoving gage-port cap.•Front-seating service valves are equipped with Schradervalves.

• 3-phase scroll compressors are rotation sensitive.• A flashing LED on phase monitor indicates reverse rotation.(See Fig. 6 and Table 3.)• This will not allow contactor to be energized.• Disconnect power to unit and interchange 2 field wiringleads on unit contactor.

Table 2—Accessory Usage

ACCESSORY

REQUIRED FORLOW-AMBIENTAPPLICATIONS(BELOW 55°F)

REQUIRED FORLONG-LINE

APPLICATIONS*(OVER 50 FT)

REQUIRED FORSEA COAST

APPLICATIONS(WITHIN 2 MILES)

Crankcase Heater Yes Yes NoEvaporator Freeze Thermostat Yes No No

Winter-Start Control Yes† No NoAccumulator No No No

Compressor Start-AssistCapacitor and Relay Yes Yes No

MotorMaster™ Control,or

Low-Ambient Pressure SwitchYes No No

Wind Baffle See Low-AmbientInstructions No No

Coastal Filter No No YesUnit Risers Recommended No Recommended

Liquid-Line Solenoid Valveor

Hard-Shutoff TXVNo

See Long-LineApplicationGuideline

No

Ball-Bearing Fan Motor Yes‡ No No

*For tubing-line sets between 50 and 175 ft, refer to Application Guideline and Service Manual—Air Conditioners and Heat Pumps Using R-22 Refrigerant.†Only when low-pressure switch is used.‡Required for low-ambient controller and MotorMaster™ Control only.

Fig. 5—Line Power Connections

A94025

DISCONNECTPER N.E.C. AND/ORLOCAL CODES

CONTACTOR

GROUNDLUG

FIELD GROUND

WIRING

FIELD POWER

WIRING

BLUE3 PHASE ONLY

4

→

→

Follow these steps to properly start up the system.

1. Fully back seat (open) liquid- and vapor-tube service valves.

2. Unit is shipped with valve stem(s) front seated (closed) andcaps installed. Replace stem caps after system is opened torefrigerant flow. Replace caps finger-tight and tighten withwrench an additional 1/12 turn for back-seating valves (malesquare stem).

3. Close electrical disconnects to energize system.

4. Set room thermostat at desired temperature. Be sure set pointis below indoor ambient temperature.

5. Set room thermostat to COOL and fan control to ON or AUTOmode, as desired. Operate unit for 15 minutes. Check system-refrigerant charge.

SEQUENCE OF OPERATION

Turn on power to indoor and outdoor units. Transformer isenergized.

On a call for cooling, thermostat makes circuits R-Y and R-G. Onthree phase models with scroll compressors, the units are equippedwith a phase monitor to detect if the incoming power is correctlyphased for compressor operation. If the phasing is correct, circuitR-Y energizes contactor, starting outdoor fan motor and compres-sor circuit. R-G energizes indoor unit blower relay, starting indoorblower motor on high speed.

NOTE: If the phasing is incorrect, the contactor will not beenergized. To correct the phasing, interchange any two of the threepower connections on the field side.

When thermostat is satisfied, its contacts open, de-energizingcontactor and blower relay. Compressor and motors stop.

If indoor unit is equipped with an off-delay circuit, the indoorblower can run up to an additional 120 sec to increase systemefficiency.

Step 11—Check Charge

UNIT CHARGE

Factory charge is shown on unit-rating plate. Adjust charge byfollowing procedure shown on charging tables located on unit.

NOTE: If superheat- or subcooling-charging conditions are notfavorable, charge must be weighed in accordance with unit-ratingplate ± 0.6 oz/ft of 3/8-in. liquid line above or below 15 ftrespectively.

EXAMPLE:

To calculate additional charge required for a 25–ft line set:

25 ft – 15 ft = 10 ft X 0.6 oz/ft = 6 oz of additional charge

COOLING-ONLY PROCEDURE

Units with Cooling Mode TXV

Unit installed with cooling-mode TXV require charging with thesubcooling method.

1. Operate unit a minimum of 10 minutes before checkingcharge.

2. Measure liquid service-valve pressure by attaching an accurategage to service port.

3. Measure liquid-line temperature by attaching an accuratethermistor-type or electronic thermometer to liquid-line nearoutdoor coil.

4. Refer to unit-rating plate for required subcooling temperature.

5. Refer to Table 4. Find point where required subcoolingtemperature intersects measured liquid service-valve pressure.

6. To obtain required subcooling temperature at a specificliquid-line pressure, add refrigerant if liquid-line temperatureis higher than indicated or reclaim refrigerant if temperature islower. Allow a tolerance of ±3°F.

Fig. 6—Phase Monitor Control

A00010

Table 3—Phase Monitor LED Indicators

LED STATUSOFF No call for compressor operation

FLASHING Reversed phaseON Normal

Table 4—Required Liquid-Line Temperature (°F)

LIQUIDPRESSURE AT

SERVICE VALVE(PSIG)

REQUIRED SUBCOOLINGTEMPERATURE (°F)

5 10 15 20

134 71 66 61 56141 74 69 64 59148 77 72 67 62156 80 75 70 65163 83 78 73 68171 86 81 76 71179 89 84 79 74187 92 87 82 77196 95 90 85 80205 98 93 88 83214 101 96 91 86223 104 99 94 89233 107 102 97 92243 110 105 100 95253 113 108 103 98264 116 111 106 101274 119 114 109 104285 122 117 112 107297 125 120 115 110309 128 123 118 113321 131 126 121 116331 134 129 124 119346 137 132 127 122359 140 135 130 125

5

→

→

→

→

Units with Indoor Pistons

Units installed with indoor pistons require charging with thesuperheat method.

The following procedure is valid when indoor airflow is within ±21 percent of its rated CFM.

1. Operate unit a minimum of 10 minutes before checkingcharge.

2. Measure suction pressure by attaching a gage to suctionvalve-service port.

3. Measure suction temperature by attaching an accuratethermistor-type or electronic thermometer to suction line atservice valve.

4. Measure outdoor air dry-bulb temperature with thermometer.

5. Measure indoor-air (entering indoor coil) wet-bulb tempera-ture with a sling psychrometer.

6. Refer to Table 4. Find outdoor temperature and evaporatorentering air wet-bulb temperature. At this intersection, notesuperheat.

7. Refer to Table 5. Find superheat temperature located in item 6and suction pressure. At this intersection, note suction-linetemperature.

8. If unit has a higher suction-line temperature than chartedtemperature, add refrigerant until charted temperature isreached.

9. If unit has a lower suction-line temperature than chartedtemperature, reclaim refrigerant until charted temperature isreached.

10. If outdoor air temperature or pressure at suction valvechanges, charge to new suction-line temperature indicated onchart.

Step 12—Final Checks

IMPORTANT: Before leaving job, be sure to do the following:

1. Securely fasten all panels and covers.

2. Tighten service valve-stem caps to 1/12-turn past finger-tight.

3. Leave User’s Manual with owner. Explain system operationand periodic maintenance requirements outlined in manual.

4. Fill out Dealer Installation Checklist and place in customerfile.

CARE AND MAINTENANCE

For continuing high performance and to minimize possible equip-ment failure, periodic maintenance must be performed on thisequipment.

Frequency of maintenance may vary depending upon geographicareas, such as coastal applications.

Table 5—Superheat Charging

OUTDOORTEMP(°F)

EVAPORATOR ENTERING AIR TEMPERATURE (°F WB)

50 52 54 56 58 60 62 64 66 68 70 72 74 76

55 9 12 14 17 20 23 26 29 32 35 37 40 42 4560 7 10 12 15 18 21 24 27 30 33 35 38 40 4365 — 6 10 13 16 19 21 24 27 30 33 36 38 4170 — — 7 10 13 16 19 21 24 27 30 33 36 3975 — — — 6 9 12 15 18 21 24 28 31 34 3780 — — — — 5 8 12 15 18 21 25 28 31 3585 — — — — — — 8 11 15 19 22 26 30 3390 — — — — — — 5 9 13 16 20 24 27 3195 — — — — — — — 6 10 14 18 22 25 29100 — — — — — — — — 8 12 15 20 23 27105 — — — — — — — — 5 9 13 17 22 26110 — — — — — — — — — 6 11 15 20 25115 — — — — — — — — — — 8 14 18 23

Where a dash (–) appears, do not attempt to charge system under these conditions, or refrigerant slugging may occur. Charge must be weighed in.NOTE: Superheat °F is at low-side service port.

6

Table 6—Required Suction-Line Temperature

SUPERHEATTEMP(°F)

SUCTION PRESSURE AT SERVICE PORT (PSIG)

61.5 64.2 67.1 70.0 73.0 76.0 79.2 82.4 85.7

0 35 37 39 41 43 45 47 49 512 37 39 41 43 45 47 49 51 534 39 41 43 45 47 49 51 53 556 41 43 45 47 49 51 53 55 578 43 45 47 49 51 53 55 57 5910 45 47 49 51 53 55 57 59 6112 47 49 51 53 55 57 59 61 6314 49 51 53 55 57 59 61 63 6516 51 53 55 57 59 61 63 65 6718 53 55 57 59 61 63 65 67 6920 55 57 59 61 63 65 67 69 7122 57 59 61 63 65 67 69 71 7324 59 61 63 65 67 69 71 73 7526 61 63 65 67 69 71 73 75 7728 63 65 67 69 71 73 75 77 7930 65 67 69 71 73 75 77 79 8132 67 69 71 73 75 77 79 81 8334 69 71 73 75 77 79 81 83 8536 71 73 75 77 79 81 83 85 8738 73 75 77 79 81 83 85 87 8940 75 77 79 81 83 85 87 89 91

7

24 VAC HOT

24 VAC COM

R

C

G

W/W1

Y/Y2

R

C

C

CARRIERNON-PROGRAMMABLE

THERMOSTATMODEL AC

SINGLE-STAGEFURNACE

AIR CONDITIONER

SEE NOTE 2

Y

G

WHEAT STAGE 1

COOL STAGE 1

INDOOR FAN

A97467

24 VAC HOT R

G

W/W1

Y/Y2

O/W2

R

W

Y

C

B

S1

S2

CARRIERPROGRAMMABLE

THERMOSTATMODEL AC

SINGLE-STAGEFURNACE

AIRCONDITIONER

G

Y1/W2

L

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

NOT USED

24 VAC COM

NOT USED

NOT USED

NOT USED

OPTIONALOUTDOORSENSORCONNECTION

C

C SEE NOTE 2

A97469

24 VAC HOT R

W

Y

G

R

W

Y

OTHERNON-PROGRAMMABLE

AC THERMOSTATSINGLE-STAGE

FURNACE AIR

CONDITIONER

C

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

CSEE

NOTE 2

G

A97367

Fig. 7—Typical 24–v Circuit Connections

24 VAC HOT

24 VAC COM

R

C

G

W/W1

Y/Y2

R

C

C

CARRIERNON-PROGRAMMABLE

THERMOSTATMODEL AC

FA, FB, FC, FD, FF

FAN COILAIR

CONDITIONER

SEE NOTE 2

G

W2HEAT STAGE 1

COOL STAGE 1

INDOOR FAN

A97468

24 VAC HOT R

G

W/W1

Y/Y2

O/W2

R

W2

C

B

S1

S2

CARRIERPROGRAMMABLE

THERMOSTATMODEL AC

FA, FB, FC, FD, FFFAN COIL

AIRCONDITIONER

G

Y1/W2

L

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

NOT USED

24 VAC COM

NOT USED

NOT USED

NOT USED

OPTIONALOUTDOORSENSORCONNECTION

C

C SEE NOTE 2

A97470

24 VAC HOT R

G

W

Y

R

C

C

OTHERNON-PROGRAMMABLE

AC THERMOSTAT

FA, FB, FC, FD, FF

FAN COILAIR

CONDITIONER

SEE NOTE 2

G

W2HEAT STAGE 1

COOL STAGE 1

INDOOR FAN

A97366

8

24 VAC HOT R

C

W/W1

Y/Y2

G

R

DH

W2

W1

Y/Y2

CARRIERNON-PROGRAMMABLE

THERMOSTATMODEL AC

FK4CFAN COIL

AIRCONDITIONER

C

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

24 VAC COM

Y1

C SEE NOTE 2

G

O

J2 JUMPER

J1 JUMPER

A97471

24 VAC HOT R

W

Y

G

R

DH

W1

W2

Y/Y2

OTHERNON-PROGRAMMABLE

AC THERMOSTATFK4C

FAN COIL AIR

CONDITIONER

C

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

Y1

CSEE

NOTE 2

G

O

J1 JUMPER

J2JUMPER

A97365

24 VAC HOT R

G

W/W1

Y/Y2

O/W2

R

DH

W1

W2

Y/Y2

C

B

S1

S2

CARRIERPROGRAMMABLE

THERMOSTATMODEL AC

FK4CFAN COIL

AIRCONDITIONER

G

Y1/W2

L

INDOOR FAN

HEAT STAGE 1

COOL STAGE 1

NOT USED

24 VAC COM

NOT USED

NOT USED

NOT USED

OPTIONALOUTDOORSENSORCONNECTION

C

Y1

O

C SEE NOTE 2

J2 JUMPER

J1 JUMPER

A97472

Fig. 7—Typical 24–v Circuit Connections (Continued)A97368

LEGEND24-V FACTORY WIRING

24-V FIELD WIRING

FIELD SPLICE CONNECTION

CONTACTORC

NOTES:1. CARRIER THERMOSTAT-WIRING DIAGRAMS ARE ONLY ACCURATE FOR MODEL NUMBERS BEGINNING WITH TSTAT__ _ _ _ _ _.2. WIRING MUST CONFORM TO NEC OR LOCAL CODES.3. SOME UNITS ARE EQUIPPED WITH PRESSURE SWITCH(ES), TEMPERATURE SWITCH, OR 5–MINUTE COMPRESSOR-CYCLEPROTECTION. CONNECT 24–V FIELD WIRING TO FACTORY-PROVIDED STRIPPED LEADS.4. THERMOSTATS ARE FACTORY CONFIGURED WITH 5–MINUTE COMPRESSOR-CYCLE PROTECTION AND 4–CYCLES–PER-–HOUR LIMIT. SEE THERMOSTAT-INSTALLATION INSTRUCTIONS FOR DETAILS.5. TO STAGE ELECTRIC-RESISTANCE HEAT, CONSULT OUTDOOR THERMOSTAT-INSTALLATION INSTRUCTIONS.6. A LIQUID LINE SOLENOID VALVE IS REQUIRED ON SOME UNITS. SEE SPECIFIC UNIT INSTRUCTIONS.

9

10

11

Copyright 2001 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231 38ckc3si

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Book 1 4Tab 3a 2a

PC 101 Catalog No. 533-80008 Printed in U.S.A. Form 38CKC-3SI Pg 12 4-01 Replaces: 38CKC-2SI